A Study on Relationship of Thermal, Electrical, and Optical Properties of an LED Light Source and Variation of Maximum Luminous Flux

Abstract Using the characteristic of flip light emitting diode (LED) chips without front-side welding wires, before applying fluorescent glue throughout the luminous surface, a part of the chips are directionally and quantitatively coated fluorescent glue by screen printing process, a chip on board (COB) white LED light source is developed with adjustable correlated color temperature (CCT). A part of the blue LED chips in the light source excites the fluorescent glue to produce a warm white light (CCT = 2631K), and the other part produces cool white light (CCT = 6181K). When changing the driving current ratio of the two parts of the chips, the CCT of COB LED light source can be continuously adjusted between warm and cool white light. According to the measured data, the relationship between the CCT and the driving current ratio of the two parts is obtained by fitting. Within the adjustable range of the CCT (2631 K to 6181 K), the color rendering index (CRI) is about 90. The minimum is 89.3 and the maximum is 93.1. While achieving adjustable CCT and high CRI, the LED light source has a luminous flux of 1938.76 lm on a circular surface with a diameter of 11 mm. The overall luminous efficiency is close to 100 lm/W.

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Carbazole-based compounds containing aldehyde and cyanoacetic acid: optical properties and applications in photopolymerization

RSC Advances ◽

10.1039/c7ra11887b ◽

2017 ◽

Vol 7 (87) ◽

pp. 55382-55388 ◽

Cited By ~ 3

Author(s):

Hussain Ahmed Abro ◽

Tengfei Zhou ◽

Weixiang Han ◽

Tanlong Xue ◽

Tao Wang

Keyword(s):

Optical Properties ◽

Light Source ◽

Cyanoacetic Acid ◽

Led Light

Carbazole-based aldehyde and cyanoacetic acid containing dyes were synthesized and applied as photosensitizers in photopolymerization with a LED light source at 455 nm.

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Electro-optical characteristics of an innovative LED luminaire with an LED matrix cooling system based on heat pipes

Semiconductor Physics Quantum Electronics & Optoelectronics ◽

10.15407/spqeo23.04.415 ◽

2020 ◽

Vol 23 (04) ◽

pp. 415-423

Author(s):

D.V. Pekur ◽

◽

V.M. Sorokin ◽

Yu.E. Nikolaenko ◽

V.P. Kostylyov ◽

...

Keyword(s):

Light Source ◽

Cooling System ◽

Renewable Energy Sources ◽

Heat Pipes ◽

Luminous Flux ◽

Optical Characteristics ◽

Led Light ◽

Lighting Systems ◽

Led Matrix ◽

Led Luminaire

Widespread use of energy-saving LED lighting systems powered by renewable energy sources, solar energy in particular, will contribute to the improvement of global ecology. One of the structural elements of such lighting systems is LED luminaire. The authors of this article perform a first ever experimental study of electro-optical characteristics of the basic version of a compact high-power LED luminaire for indoor use. The particular feature of this lighting device is that its cooling system for the LED light source is based on heat pipes and concentric cooling rings. Such design allows ensuring the required cooling efficiency of the LED matrix. The revealed trends in optical and electrical parameters during temperature stabilization indicate that the proposed cooling system is highly efficient in maintaining normal thermal conditions of LED light sources with a power of up to 140.7 W and a luminous flux of up to 15083 lm. The results on determining spatial distribution of luminous flux of these luminaires indicate that they may be used for lighting large rooms with high ceilings. Scaling the basic modular design version of the cooling system allows increasing the power of the LED light source up to 600 W.

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Influence of Encapsulated Silica Gel on Output Luminous Flux of Deep Sea LED Light Source

Chinese Journal of Luminescence ◽

10.37188/cjl.20200196 ◽

2020 ◽

Vol 41 (10) ◽

pp. 1302-1308

Author(s):

Tong CHEN ◽

◽

Fei WANG ◽

Lu-qiao YIN ◽

Jian-hua ZHANG

Keyword(s):

Light Source ◽

Silica Gel ◽

Deep Sea ◽

Luminous Flux ◽

Led Light

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Iterative Model for Simulating Light Intensity Variation of LED

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.364-366.789 ◽

2007 ◽

Vol 364-366 ◽

pp. 789-794 ◽

Cited By ~ 1

Author(s):

Hong Liu ◽

Yan Nan Shen ◽

Qiong Chen

Keyword(s):

Light Intensity ◽

Light Source ◽

Engineering Application ◽

Intensity Variation ◽

Luminous Flux ◽

Calculation Error ◽

Light Sources ◽

Luminous Efficacy ◽

Led Light ◽

Iterative Model

As a new kind of light source, LED light source has found wide application in many fields, especially in automotive lamp light source with the rise of luminous efficacy. The paper puts forward an iterative model, which approximates the light intensity variation of LED by adding up a series of the luminous flux of sub light sources with uniform light intensity, and accurately reflects the attenuation feature of LED light intensity. As long as the tracing ray is sufficient, the calculation error will be very small, and the result ideal, thus making it suitable for engineering application.

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